Signature inserter

ABSTRACT

A signature inserter for a signature gathering machine having two hoppers, arranged one above the other; two rotary extractor drums, each of which is associated with one hopper and provided with means for extracting individual signatures from that hopper; a rotary transfer drum for transferring individual signatures from one extractor drum to the conveyor and a rotary intermediate drum for transferring signatures from the other extractor drum to the first extractor drum. Finally, the signature inserter includes means for selecting the hopper from which the signatures will be extracted.

United States Patent [191 Lachman et al.

[451 Apr. 23, 1974 SIGNATURE INSERTER [75] Inventors: Louis A. Lachman,Princess Anne,

Md.; Warren D. Reinert, York; Richard W. Le Grand, Wayne, both of Pa.

[73] Assignee: John C. Motter Printing Press Co.,

York, Pa.

[22] Filed: Sept. 27, 1972 [21] App]. No.: 292,680

[52] US. Cl. 270/54, 271/9 [51] Int. Cl B65h 39/04 [58] Field of Search270/54-58; 271/9 [56] References Cited UNITED STATES PATENTS 3,523,6858/1970 Ehlschide 271/9 3,371,924 3/1968 Nelson et al.. 270/58 X2,855,195 l0/l958 Young 270/54 3,692,300 9/l972 Mebus 270/55 3,032,3365/1962 Heigl et al. 270/53 931,099 8/1809 Ubham 27l/9 2,603,483 7/1952Fischer et al. 271/9 Primary Examiner-Robert W. Michell AssistantExaminerL. R. Dremlant 57 ABSTRACT 7 Claims, 21 Drawing FiguresTATEMEUAPR 23 1974 11%. 8 06; l l l SHLU 8 BF 8 A I y 202 I92 84 d 1uPPER 200 '96 HOPPER VACUUM SOLENOID ROTARY SUCTION CONTROL SOURCE'VALVES VALVES CUPS l l f I LOWER I HOPPER A V MECHANICAL I98 I I DRIVE3- L F/G. /0

F/G. //0 F/G. //b

F/G. //0' FIG. //6 FIG. //f

[ HO F ER v v v 252 Nc VALVE VACUUM f\ f I\ f f\ IL 3262 1 1 NC VALVE266 272 All HOPPER n A 202 1% r\ 12k SIGNATURE INSERTER BACKGROUND OFTHE INVENTION The present invention relates generally to signaturegathering machines of the type in which signatures are extracted insuccession from a plurality of hoppers and inserted on a conveyor toassemble a book.

More particularly, this invention concerns a portion or unit of asignature gathering machine known as a signature inserter. A signatureinserter removes individual signatures from a hopper and transfers themto the conveyor in timed relation to the movement of the conveyor. Sinceeach signature inserter conventionally feeds signatures to the conveyorfrom a single hopper, the signature gathering machine requires as manyinserters, arranged side by side, as hoppers (signatures) are requiredto form the book.

Particularly in the case of periodicals which are sold to a large numberof subscribers, it is useful to divide the subscribing publicdemographically into a plurality of classes and to tailor the periodicalto each specific class. For example, the subscribing or purchasingpublic may be classified by place of residence, by occupation, by ethnicorigin, by sex, by income or by some other useful demographic breakdownwhich is relevant either to reading preference or to purchasing habitsor both. It is generally recognized that a periodical, such as amagazine, would be much more effective in conveying information and as amedium of advertising if it could be prepared with a specific readingpublic in mind. Until recently the formation of demographically orientedperiodicals has been but a futuristic goal; very little machinery hasbeen designed to effectuate this proposal.

Books, a term used in the printing art to include magazines, catalogs,pamphlets and the like, as well as conventional books, are composed ofsignatures which are simply folded sheets bearing printed matter. Thesignatures may present pages of the usual format,

or they may constitute inserts of a special size. Theindividualsignatures which compose the book are fed from hoppers in a signaturegathering machine and deposited or collected one atop another on aconveyor. The collected signatures are then transported by the conveyorto a station where they are joined into a book by stitching (forexample, with staples) or by gluing,

depending upon how the book is bound.

The signature gathering machine thus includes the conveyor and a numberof units or signature inserters" arranged side by side. In theconventional arrangement, each inserter supplies signatures to theconveyor from a single hopper so that if each book is to be identical,one signature inserter is required for every signature inserted in thebook.

If the books are to be tailored to separate demographic classes ofreaders, it is necessary to select and insert a particular one of aplurality of alternative signatures at certain places in the book. Theselection of signatures for an individual book or series of books hasconventionally been effected in one of two ways:

1. A first series of books are formed on a signature gathering machinewith a first set of signatures arranged in the hoppers of the machine.The operation of the machine is then interrupted while the signatures inone or more hoppers are replaced by different signatures. A secondseries of books are then formed on the machine from the second set ofsignatures, and so on. Obviously, the number of demographic series whichcan be generated in this way is limited since the machine must bestopped and the hoppers refilled for each separate run.

2. A signature gathering machine is employed which is much longer, inthe direction of the conveyor, and contains more hoppers than wouldotherwise be necessary. Means are provided to inhibit the transfer ofsignatures from individual hoppers to the conveyor so that books may beformed from selected signatures, as desired. Obviously this arrangementlengthens the signature gathering machine considerably, requiringadditional machinery, additional floor space, and even additionalpersonnel to supply the signatures and supervise the operation of themachine. For example, in order to permit selection between twoalternatives for each signature in a book, it is necessary to double thenumber of signature inserters and double the length of the conveyor.

SUMMARY OF THE INVENTION It is an object of the present invention,therefore, to provide a signature gathering machine capable ofassembling books distinctively formed for different demographic classesof readers, which machine does not exhibit the disadvantages of theconventional signature gathering machines described above.

This object, as well as other objects which will become apparent in thediscussion that follows, is achieved, according to the presentinvention, by providing the signature gathering machine with one or moresignature inserters having at least two signature hoppers from whichsignatures may be fed to the conveyor. Means are provided for eachmulti-hopper inserter to permit selection of the hopper from which asignature or signatures are to be extracted.

In a preferred embodiment of the present invention, the signaturegathering machine is comprised of one or more signature inserters havingtwo signature hoppers arranged one above the other. Although additionalhoppers may be provided, arranged in a substantially vertical row,convenience in filling the hoppers with signatures prescribes alimitation -on the number of hoppers per machine.

The signature inserter according to the preferred embodiment of thepresent invention thus comprises two hoppers, arranged one above theother; two rotary extractor drums, each of which is associated with onehopper and provided with means for extracting individual signatures fromthat hopper; a rotary transfer drum for transferring individualsignatures from one extractor drum to the conveyor and a rotaryintermediate drum for transferring signatures from the other extractordrum to the first extractor drum. Finally, the signature inserterincludes means for selecting the hopper from which the signatures willbe extracted.

The selection means for controlling the extraction of signatures fromthe two hoppers preferably comprises at least one suction cup associatedwith and movable toward and away from the supply of signatures in eachhopper for selectively withdrawing at least the leading edge of theleading signature in the hopper when a vacuum is applied. Control means,including a source of vacuum, is provided for. selectively applying thevacuum to the appropriate suction cups in timed relation to theoperation of the machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view,partly in section, of a signature inserter constructed in accordancewith the present invention.

FIG. 2 is a diagrammatic end view of a typical signature showing therelative lengths of the legs thereof.

FIG. 3 is a side elevational view of the intermediate drum of thesignature inserter shown in FIG. 1. FIG. 3a is a side elevational viewof the intermediate drum showing a modification thereof.

FIGS. 4 and 4a are end elevational views of the intermediate drum shownin FIGS. 3 and 3a, respectively.

FIG. 5 is a side elevational view of a portion of the upper extractordrum of the signature inserter shown in FIG. 1.

FIG. 6 is an end elevational view of the extractor drum of FIG. 5.

FIG. 7 is a diagrammatic view of a first modification of the signatureinserter shown in FIG. 1.

FIG. 8 is a diagrammatic view of a second modification of the signatureinserter shown in FIG. 1.

FIGS. 9a and 9b are side and end elevational views, respectively,of athird modification of the signature inserter shown in FIG. 1.

FIG. 10 is a block diagram of the control system of the signatureinserter shown in FIG. 1.

FIGS. Ila-11f are diagrammatic views illustrating the operation of thesignature inserter shown in FIG. 1.

FIG. 12 is a schematic diagram of a logic circuit which may be employedin the control system shown in FIG. 10.

FIG. 13 is a timing diagram illustrating the operation of the logiccircuit shown in FIG. 12.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments ofthe present invention will now be described with reference to FIGS. l-13in the drawings. Like elements which are depicted in the various figuresare designated with the same reference numerals.

FIG. 1 illustrates one preferred embodiment of the signature inserteraccording to the present invention. This inserter functions in asignature gathering machine to repetitively insert signatures onto asaddle type conveyor of conventional design. The conveyor is arranged tomove successively past a plurality of signature inserters and therebycollect signatures to repeatedly form a' book. A signature inserter ofthe general type to which the present invention relates is disclosed,for example, in the U.S. Pat. No. 2,413,358 to Kleineberg.

The signature inserters in a given signature gathering machine may beeither the conventional type which feed signatures to the conveyor froma single hopper, or they may be the multi-hopper signature inserteraccording to the present invention.

As illustrated in FIG. 1; the signature inserter according to thepreferred embodiment of the present invention includes, essentially,upright frames 10 having a base 12; an upper hopper 14 and lower hopper16 for the supply of signatures 18 and 20, respectively; a shelf 22 forjogging and storing fresh supplies of signatures;

an upper extractor drum 24 for withdrawing signatures from the upperhopper 14; a lower extractor drum 26 for withdrawing signatures from thelower hopper 16; a transfer drum 28; an intermediate drum 30; an openerdrum 32; and a stationary saddle or bayonet 34 from which signatures maybe received by a saddle type conveyor 36. Alignment of the frame 10 ismaintained by frame rods 38 which extend the full length of the machine.Not shown, but extending parallel to the rods 38are lines or'pipes whichprovide the machine with compressed air and vacuum. A rectangular duct40 extends along the top of the machine to house the wires providing theelectric controls.

Also extending lengthwise of the machine are a main drive shaft 42; ajack shaft 44; an upper extractor drum shaft 46; a lower extractor drumshaft 48; an upper cam shaft 50; an intermediate cam shaft 52; a lowercam shaft 53; a transfer drum shaft 54; an intermediate drum shaft 56;and an opener drum shaft 58. A timing chain or belt 60 leads from asprocket on thedrive shaft 42 to a sprocket 62 fixed to the jack shaft44. A second sprocket 64 on the jack shaft cooperates with a drive chainor belt 66 to transmit power to the upper and lower extractor drumshafts 46 and 48, and to the upper, intermediate and lower cam shafts50, 52 and 53. The intermediate drum shaft 56 is driven by a chain orbelt 68 from the intermediate hopper cam shaft 52. The opener drum shaft58 is driven by another chain or belt 70 from the transfer drum shaft54. Various guide sprockets 72 are provided for the timing chain 60 andthe drive chains 66 and 70.

The signature inserter operates in timed relation with the movement ofthe saddle conveyor 36. Each time the outstanding cars 74 on theconveyor 36 move a signature off the stationary saddle 34 onto theconveyor, the signature inserter completes a new cycle to place anothersignature on the saddle. A cycle of the machine is thus completedbetween the time that a signature 'is deposited on the saddle 34 and thetime that the subsequent signature is so deposited. As will becomeappar: ent from the discussion of machine operation hereinbelow, themachine requires one complete revolution of the transfer drum 28 andopener drum 32 for each cycle of operation. Similarly, the machinerequires one complete revolution of the intermediate drum 30 and the camshafts 50 and 52 per cycle. The extractor drums 24 vand 26 must make acomplete revolution for every two cycles of operation; accordingly, theextractor drums are driven at half the speed of the transfer drum,opener drum, intermediate drum and cam shafts.

The bottom wall of the hoppers 14 and 16 is formed by an endless belt orbelts 76, suitably supported at 78 by the frame 10 and driven in thedirection indicated in FIG. I to urge the signatures resting thereonagainst the forward walls 80 and 82 of upper and lower hoppers,respectively. The belts 76 may be moved continuously but are preferablydriven only upon detecting the absence of a signature in the forwardposition; i.e., in the demand feed" mode. Chains or wires may, ofcourse, be substituted for the belts 76.

Pivotally attached near the lower end of the front walls 80 and 82 ofthe upper and lower hoppers, respectively, are suction cups 84 and 86which function to draw signatures out of the hoppers by application ofvacuum. Since two or more suction cups are normally. arranged at eachhopper in parallel, a vacuum is applied to the cups simultaneouslythrough a common manifold 88 (in the case of the suction cups 84) andmanifold 90 (in the case of the suction cups 86) extending lengthwise ofthe machine. Pivotal motion is imparted to the suction cups about theirrespective manifolds by a cam operated mechanism (not shown) actuated bythe corresponding cam shafts 50 and 52. The suction cups 84 and 86 arealternately swung outwardly into engagement with the foremost signaturein the respective hoppers and then inwardly toward the respectiveextractor drums 24 and 26. If a vacuum is applied to the suction cups,they will adhere to and pull the lower end of the foremost signature outof the hopper during the inward swing.

Rotation of the extractor drums 24 and 26 is timed relative to thepivotal motion of the suction cups 84 and 86 such that, when the cupsare in the inward position, the fingers 92 and 94 carried by theextractor drums 24 and 26 close on the leading end of the foremostsignature and clamp it against a seat 96 or 98 on the drum. Continuedrotation of the drums 24 and 26 then causes the signature to be pulledfrom the hopper by its leading end. As is depicted generally in FIG. 1and with more particularity in FIG. 2, the signatures 100 are normallypositioned in the hoppers 14 and 16 with their closed end 100a extendingdownward, so that the closed end becomes the leading end clamped by theextractor drum. So positioned, the long leg of the signature is arrangedforward of the short leg 100a so that it will come in contact with theextractor drum when withdrawn from the hopper. The purpose for thisorientation of the signatures in the hoppers will become clear in thediscussion which follows.

As is conventional in signature. inserters of a signature gatheringmachine, the gripper fingers 92 and 94 are automatically closed at theproper timed relation relative to the movement of the suction cups 84and 86, respectively, so that a signature is gripped each time thefingers pass suction cups to which a vacuum has been applied. Currentpractice is also to extract two signatures from a hopper on eachrevolution of an extractor drum. For this purpose, a second set ofgripper fingers 92a and 94a and cooperating seats 96a and 98a,respectively, are located on each extractor drum diametrically oppositeto the first set of fingers 92 and 94. Each set of fingers 92, 92a, 94and 94a is, of course, operable to close upon the leading end of asignature as it moves past the extracting position.

The fingers 92, 92a, 94, and 94a are actuated by cam-followingmechanisms which, for the sake of clarity, are not shown in FIG. 1.

In the embodiment illustrated in FIG. 1, and in accordance with theprinciples of the present invention, the intermediate drum 30 is alsoprovided with gripper fingers 102. These fingers clamp the leading endof a signature against a seat 104 as this leading end is brought tangentto the intermediate drum by the lower extractor drum 26. Upon clampingthe signature by the gripper fingers 102, the gripper fingers 94 or 94aof the lower extractor drum 26 are released. The signature is thenbrought upward on the periphery of the intermediate drum toward theupper extractor drum 24.

When the leading edge of the signature gripped by the fingers 102 on theintermediate drum reaches the upper extractor drum, it is clamped by asecond set of gripper fingers 106 or 106a on the upper extractor drumwhich pivot about the same axes as the fingers 92 and 92a, respectively.Like the fingers 92 and 92a, the fingers 102, 106 and 1060 are actuatedby camfollowing mechanisms which, for the sake of clarity, are not shownin FIG. 1.

The cam-following mechanism for the fingers 102 will be discussed belowin connection with FIGS. 3 and 4, and the cam-following mechanisms forthe fingers 92, 92a, 106, and 106a will be discussed in connection withFIGS. 5 and 6. Suffice it to say, at this point, that the fingers 92 and92a automatically close against their respective seats whenever theypass the suction cups 84 and the fingers 106 and 106a automaticallyclose whenever they pass the intermediate drum 30. The fingers 92, 92a,106 and 106a are simultaneously raised sufficiently to release asignature as the leading edge of the signature enters the upperleft-hand quadrant of the upper extractor drum.

The dual sets of gripper fingers 92, 92a, 106, and 106a are thereforeoperative to clamp a signature originating from either the upper hopper14 or the lower hopper 16. If signature is not drawn out of the hopper14 by the section cups 84, the gripper fingers 92 and 92a will merelyclose against their respective seats 96 and 96a without clamping asignature. In this case, the machine will function to deliver asignature from the lower hopper 16 via the second extractor drum 26 andthe intermediate drum 30. As the gripper fingers 106 or 106a pass theintermediate drum 30 they will clamp a signature against a respectiveseat 96 or 960.

Upon continued rotation of the upper extractor drum 24, the signature iscarried by the drum until the lead ing end of the signature abutsagainst a notched stop 108 fixed to an arm 110 extending from the shaft46. The stop 108 locates the trailing end of the signature at the properposition or point to be gripped by and transferred to the transfer drum28.

In FIG. 1, a signature 1 12 is illustrated in the stop position. Duringits travel from either the upper hopper 14 or the lower hopper 16 to thestop position, the leading end of the signature 112 is supported by twogenerally cylindrical extractor drum sections 24a (only one of which isshown) that are spaced axially'on the shaft 46. The body of thesignature and its trailing ends are supported between the extractor drumsections on one side and signature guides (not shown) on the other tokeep the signature from flying outward by centrifugal force. Thesesignature guides may be either solid, preferably chromium plated railsor constructed of brushes.

Since the point of transfer of these signatures from the extractor drum24 to the transfer drum 28 is fixed, provision is made to adjust theposition of the stop 108 to account for variations in the width of thesignatures being inserted on the conveyor 36. Thus, the upper end of thearm 110 is adjustably received in an arcuate slot 114 formed in abracket 116 conveniently anchored near the front wall of the upperhopper 14. By moving the arm along the slot 114, the position of thesignature stop 108 may be adjusted so that signatures of different widthmay be handled without variation in the location of the point where thetrailing ends of these signatures come to rest when the signatures arestopped.

To ensure that the signature 1 12 will fully engage the stop 108 andwill remain in the stop position until gripped by the transfer drum 28,a guide roll 118, pivoted on the arm 110 and spring-biased toward theextractor drum 24, bears against the signature 112 causing it to beurged by frictional engagement with the surfaces of the drum sections24a into contact with the stop 108. In accordance with conventionalpractice, the gripper fingers 92, 92a, 106, 106a are opened just beforethe leading end of the signature reaches the stop 108. A second guideroll 120, adjustably mounted on a frame rod 38, prevents the trailingend of the signature from flying outward away from the extractor drum 24and, by bending the signature during the transfer phase, helps to openthe legs thereof prior to gripping by the opener drum 32.

The transfer drum 28 is illustrated and described in detail in thecopending US. Pat. application Ser. No. 234,076 filed Mar. l3, 1972 byWarren D. Reinert. Briefly, this transfer drum includes two axiallyspaced drum sections 28a (only one of which is shown) each arrangedadjacent to, but off-set axially from, a corresponding extractor drumsection 24a. Each section 28a is divided circumferentially into twosegments, one segment 122 of relatively short radius, and anothersegment 124 of larger radius.

The radius of the segments 124 on the two axially spaced transfer drumsections 28a is such that these segments will enter within, i.e.,overlap, the periphery of the extractor drum sections 24a when thesegments 124 are in the region of closest approach to the axis of thefirst extractor drum 24. Due to their smaller radius, the segments 122of the transfer drum sections 28a will remain outside the periphery ofthe extractor drum sections 24a spaced by at least the thickness of asignature. The rotational timing of the extractor drum 24 and thetransfer drum 28 is such that when a signature is being carried by theextractor drum 24 past the transfer drum 28, the short radius segments122 are adjacent to the extractor drum, thus allowing a signature to bemoved between the drums without interference and to be brought intoengagement with the notched stop 108. Immediately thereafter, thesegments of 124 of larger radius enter within the extractor drum 24behind the trailing end of the signature, as depicted in FIG. 1.

When the segments 124 of larger radius of the transfer drum 28 haverotated around to the position shown in FIG. 1, the two legs of thesignature which has abutted the stop 108 are clamped against a seat 126by short and long gripper fingers 128 and 130, respectively. The longgripper fingers 130 press both legs of the signature against the seat126 whereas the short gripper fingers 128 press only the longer leg ofthe signature against the seat. Upon continued rotation of the transferdrum 28, the signature is pulled off the extractor drum 24 in reversedirection i.e., trailing end first and is moved toward the opener drum32. I

The transfer drum 28 and the opener drum 32 thereafter coact, in a knownmanner, to open the legs of the signature so that the signature may bedelivered in straddling fashion to the stationary saddle 34. Thus, at

, a predetermined point in the approach of the trailing end of thesignature toward the opener drum 32, the longer gripper fingers 130 ofthe transfer drum 28 are opened releasing the short leg of thesignature, while the shorter fingers 128 remain closed, holding the longleg of the signature against the seat 126.

Shortly thereafter, the short leg of the signature is clampedmomentarily by gripper fingers 132 against a seat 134 on the opener drum32. With the short leg thus gripped by the opener drum 32 and the long'leg gripped by the transfer drum 28, the signature legs are spreadapart as the drums 28 and 32 rotate beyond the gripping point. Whenopening of the signature has-progressed to an extent that it willstraddle the saddle 34,

the short fingers 128 of the transfer drum 28 and the.

fingers 132 of the opener drum 32 are opened, releasing both signaturelegs. Positive, non-slip feeding of the signature to the saddle 34 iseffected by a layer of resilient material (not shown) provided on theopener drum surface to press the signature body between the opener drumand the large radius segments 124 of the transfer drum 28.

The stationary saddle 34 is suspended from the machine frame 10 by abracket and extends forwardly in the direction of movement of theconveyor 36. As the conveyor 36 progresses from'station to station alongthe length of the signature gathering machine, it collects a signaturefrom the stationary saddle of each signature inserter. This isaccomplished by the outstanding cars 74 located at equidistant intervalsalong the conveyor. As the ears 74 move beneath a saddle, they strip thesignature from the saddle so that the signature comes to rest on theassociated conveyor saddle 136 or on the signatures collected by theconveyor at previous stations. In this way, a new signature is added toeach moving saddle 136 until a complete book has been assembled.

As shown in FIG. 1, the overall length of the signature inserter may bereduced, thereby conserving floor space in the bindery, by positioningthe transfer drum 28 optimally relative to the upper extractor drum 24and the other machine components. The transfer drum 28 and its shaft 54are preferably located such that their common axis of rotation liesbelow the first extractor drum 24 in a plane A-A which is tangent to theperiphery of the extractor drum 24 and inclined at approximately 21 20angle counterclockwise fromthe vertical. While a 20 angle is optimum,other inclinations may also be employed to advantage.

Similarly, the intennediate drum 30 and its shaft 56 as well as thelower extractor drum 26 and its shaft 48 are preferably located suchthat their axes of rotation are below the upper extractor drum 24 andlie in a plane 'B--B which passes through the axis of the upperextractor drum. The plane BB is inclined at approximately a 30 anglecounterclockwise from the vertical so that the intermediate and transferdrums are separated slightly and the lower hopper 16 is moved outward(below the shelf 22) for easier access. While a 30 angle is optimum forthe plane B B, other inclinations may also be employed to advantage.

Finally, the upper cam shaft 50, intermediate cam shaft 52 and the lowercam shaft 53 are preferably located such that their axes of rotation areequidistant from each other and lie in a plane C-C which is parallel tothe plane BB. This permits the use of interchangeable parts (not shown)in the hopper feed and signature withdrawing mechanisms.

FIGS. 3 and 4 illustrate the intermediate drum 30 in greater detail. Asmay be seen in side viewin FIG. 3 and in end view in FIG. 4,'the gripperfingers 102 are arranged at the ends of a shaft 138 which is pivoted forrotational movement in the two sections 30a of the intermediate drum.The shaft 138, and consequently the gripper fingers 102, are biased inthe direction of closing by a tension spring 140 connected between a pin141 protruding from one of the drum sections 30a and a crank arrangement142 mounted on one end of the shaft 138. The shaft 138, and consequentlythe gripper fingers 102, are rotated to an open position by a cammechanism comprising a cam 143 and cam follower 144. The cam follower isrotatively mounted on a crank arm 145 which is attached to the oppositeend of the shaft 138.

The cam 143 is held stationary with respect to the machine frame bymeans of bolts 146. The angular position of the cam may be adjusted,within limits, by loosening the bolts and rotating the cam about itsaxis, As the cam is rotated, the bolts slide in slots 147 of astationary member 148. Tightening the bolts retains the cam against thestationary member.

The profile of the cam 143 is designed to open the gripper fingers 102as these fingers approach the upper extractor drum 24 and to allow thegripper fingers 102 to close as they approach the lower extractor drum26. When in the closed position, the spring mechanism 140-142 maintainsa clamping pressure such that, if a signature is clamped, the forces ofinertia and centrifical force cannot withdraw the signature from betweenthe gripper fingers I02 and the seats 104.

FIGS. 3a and 4a show a modification of the gripper fingers 102 and seats104 which may be incorporated in the intermediate drum 30 of the presentinvention to provide a more positive, non-slip grip of the signatures.In this case, a small needle 149 is arranged in each seat 104 toprotrude slightly from the exterior surface thereof at the tip of eachgripper finger 102. To ensure that the gripper fingers 102 will not comeinto contact with the needles 149, a small notch 150 is cut in the tipof the fingers surrounding the needles 149.

Operation of the gripper fingers with the modified embodiment of FIGS.3a and 4a is identical to that described above for the embodiment ofFIGS. 3 and 4.

FIGS. 5 and 6 show the mechanisms for operating the gripper fingers 92and 106 on the upper extractor durm 24. As discussed above in connectionwith FIG. 1, the gripper fingers 92 operate to close as they pass thevacuum cups 84 associated with the upper hopper 14, while the gripperfingers 106 operate to close as they pass the intermediate drum 30. bothsets of gripper fingers 92 and 106 are opened simultaneously when theyreach the signature stop 108.

The mechanism for closing and opening the gripper fingers 92 and 106 issimilar to the actuating mechanism for the gripper fingers 102 of theintermediate drum 30 discussed above in connection with FIGS. 3 and 4.The gripper fingers 92 are arranged at the ends of a shaft 151 which ispivoted for rotational movement in the two sections 24a of the extractordrum. The gripper fingers 106 are connected to a second, hollow shaft152 which is pivoted for rotation about the shaft 151 between thesections 24a of the extractor drum.

The apparatus for rotating the shafts 151 and 152, and thus actuatingthe gripper fingers 92 and 106, respectively, is arranged at oppositeends of the extractor drum. The shaft 151 is rotated by a gear 153 whichis turned by a gear segment 154 pivoted on pin 155 extending through theadjacent drum section 24a. The gear segment 154 is biased in a directiontending to close the gripper fingers 92 by a compression spring 156 andis rotated in a direction tending to open the gripper fingers 92 by acam follower 157 which rides on a stationary cam 158.

The shaft 152 is rotated in a similar manner by a gear 159, gear segment160, compression spring 161, cam follower 162 and stationary cam 163.The compression spring 161 and cam follower 162 act on a pivot arm 164which operates to rotate a pin 165 extending axially through theadjacent drum section 24a.

The relationship between the upper extractor drum 24 and theintermediate drum 30 is also illustrated in FIG. 5. As shown in dashedlines, the intermediate drum 30 is arranged between sections and gripperfingers of the upper extractor drum to avoid contact between themechanical parts.

The gripper fingers 94 of the lower extractor drum 26 may be actuated byan arrangement identical to the mechanism for operation the gripperfingers 92 of the upper extractor drum, described above.

FIGS. 7, 8 and 9 illustrate modifications which may be made to theapparatus of FIG. 1. In FIG. 7 the lower extractor drum 26 and theintermediate drum 30 are each provided with at least one roller 168 thatis mounted for rotation on an arm 170 pivoted on the frame at 172 andbiased by a spring 174 or other suitable means in the direction of therespective drum. The rollers 168 thus maintain a non-slip pressureagainst each signature which is carried on the extractor drum 26 andintermediate drum 30 permitting the gripper fingers of the extractordrum 26 and intermediate drum 30 to be opened prior to the instant thatthe signature is to be released. Thus, for example, the gripper fingers102 of the intermediate drum 30 may be opened as soon as they passbeneath the roller 168 which presses against the intermediate drum.

FIG. 8 illustrates an alternative arrangement whichmay be used in theapparatus of FIG. 1 to hold a signature against the intermediate drum30. This arrangement consists of a plurality of belts 176 extended aboutrollers 178 so as to .wrap around a segment of the intermediate drum 30.If desired, an additional group of belts 180 arranged on rollers 182 maybe employed in conjunction with the lower extractor drum 26 to directthe signature to the point where it is received by the intermediate drum30. A signature received by the intermediate drum is pinched between thebelts 176 and the drum sections 30a and carried upward to the upperextractor drum 24.

The belts 176 and 180 are preferably driven at the same speed as thecircumferential surfaces of the extractor drum 26 and intermediate drum30 by a suitable one of their respective rollers 178 and 182.

FIGS. 90 and 9b illustrate, in side and end views, respectively, anotherpossible modification of the apparatus of FIG. 1. In this embodiment,the intermediate drum 30 comprises a single drum body 183 having aplurality of openings 184 for the passage of air. A separate disk orshoe 186, is arranged adjacent the drum body, and provided with a portor chamber 188 connected to a vacuum line 190. A vacuum established inthe line 190 causes air to be drawn from the chamber 188 and from any ofthe openings 184 which are aligned therewith. A vacuum is thereforeestablished along a certain sector of the outer periphery of theintermediate drum 30 causing any signature which may be situated alongthis sector to adhere to the drum.

The chamber 188 extends approximately halfway around the disk 186. Asthe openings 184 rotate past the chamber (in the direction indicated bythe arrow), they pass a bleeder hole 187 in the disk 186. This holecauses the vacuum in the openings to disappear so that the signatureadhering to the drum may be easily removed.

Like the cams described above in connection with the gripper fingeractuating mechanism, the disk 186 is stationary with respect to themachine frame 10. It is anchored to the frame by means of a brace 189which may, for example, be attached to one of the frame rods 38. Thebrace 189 is provided with a slot 191 to permit rotational adjustment ofthe disk 186.

FIG. is a block diagram of a preferred system for selecting andcontrolling the withdrawal of signatures from the two hoppers 14 and 16of the signature inserter of FIG. 1. As explained above in connectionwith FIG. 1, the selection of signatures is effected by the timedapplication of vacuum to the suction cups 84 and 86. These cups arecaused to swing toward and away from the signatures l8 and 20 arrangedin the upper and lower hoppers 14 and 16, respectively; and, when vacuumis applied, they operate to draw the leading signature inward toward theadjacent extractor drum. When the signature is clamped by the gripperfingers of the extractor drum, the vacuum is removed so that thesignature may be easily drawn away from the suction cups. After thetrailing end .of the signature has passed the suction cups, the cups arepivoted back toward the hopper and, if another signature is to bewithdrawn, the vacuum is applied again.

In the conventional signature inserter having only one hopper, thevacuum is intermittently applied to the suction cups in timed relationto the position of the extractor drum by means of a valve connectedbetween the source of vacuum and the suction cups. Such a valve may, forexample, be a rotary valve of the type disclosed in the U.S. Pat. No.3,610,281 issued Oct. 5, 1971 to Warren D. Reine'rt. In the signatureinserter according to the invention, two such rotary valves 192 and 194are used in conjunction with the cups 84 and 86 at the upper hopper andlower hoppers, respectively. These valves are connected between a vacuumsource 196 and the suction cups as shown in FIG. 10.

The rotary valves 192 and 194 are mounted onthe cam shafts and 52,respectively, in the signature inserter of FIG. 1 and are rotated at thesame speed as the intermediate and transfer drums by the drive mechanismindicated generally in FIG. 10 at 198.

In addition to the rotary valves, the vacuum to the suction cups iscontrolled by a logic circuit 200 connected electrically to two solenoidvalves 202 and 204 arranged in the vacuum lines between the vacuumsource and the suction cups 84 and 86, respectively. Like the rotaryvalves, the logic circuit 200 receives an input from the mechanicaldrive l98.ln' addition, the A logic circuit is responsive to switches orpush buttons which permit an operator to select whether the signaturesare to be extracted from the upper hopper or lower hopper. If thesignature inserter is used in a fully automated signature gatheringmachine, the logic circuit 200 may receive signals from a master controlunit which automatically selects the hopper from which signatures are tobe withdrawn. Such a master control unit is particularly useful if theindividual books formed by the signature gathering machine are to differaccording to the demographic classification. of the readers to whom thebooks will be directed. I

the structure and operation of an exemplary logic circuit 200 will bedescribed below in connection with FIGS. 12 and 13. Before discussingthis circuit in detail,

however, it will be useful to consider the operation of the signatureinserter and, specifically, to consider its operation when the machineis switched from a mode in which signatures are extracted from the upperhopper to a mode in which they are extracted from the lower hopper, andvice-versa. This operation will now be explained with reference to FIG.11.

As has been explained above in connection with FIG. 1, the intermediateand transfer drums of the signature inserter are rotated one completeturn during each cycle of machine operation. The period of one machinecycle is thus equivalent to the time between the instants thatsuccessive signatures are dropped onto the saddle 34. During this periodthe conveyor 36, which gathers signatures into books, moves from onestation or signature inserter to the next or, after passing allstations, delivers a completed book at the end of the signaturegathering machine. The machine cycle of the signature inserter istherefore identical to the book cycle of the signature gathering machineand these two terms will hereinafter beused interchangeably.

FIGS. Ila-11f diagrammatically show the' principal functional elementsof the signature inserter illustrated in FIG. 1. In each figure there isshown the upper and lower hoppers l4 and 16, the upperand lowerextractor drums 24 and 26, the transfer drum 28, the intermediate drum30 and the opener drum 32. In each extractor drum 24 and 26 there is acircle 206 and 208, re.- spectively, which represents the vacuum linecon nected to the associated suction cups. If an X appears in thecircle, as it does, for example, in the circle 206 in FIG. 11a, thissignifies that a vacuum is applied to the suction cups for thatextractor drum and hopper. If an X is absent, as in the case of circle208 in FIG. 11a, this signifies that vacuum is not applied to thecorresponding suction cups. Specifically, ,if an -X is present, then thesolenoid valve connecting the vacuum source to the corresponding suctioncups is open, and if an X" is absent, the solenoid valve connecting thevacuum source to the correspondingsuction cups is closed. I

FIGS. 1 la-Il illustrate the signature inserter at successive moments intime as the signature inserter is switched from the mode of operation inwhich it withdraws signatures from the upper hopper 1 4 to the mode ofoperation in which it withdraws signatures from the v v lower hopper 16.Each successive figure shows the signature inserter atapproximatelyone-half book cycle later in time.

In FIG. 11a the vacuum is applied to the suction, cups of the upperhopper 14 as indicated by the X in the circle 206. At the illustratedmoment in time, the signature inserter has withdrawn a signature 210from the upper hopper and is about to withdraw another.

In FIG. 1 1b the upper extractor drum has rotated approximately onequarter turn, carrying the signature 210 upward to a position where itstrailing end may be clamped by the transfer drum. Sincethe vacuum hasbeen maintained at the suction cups at the upper hopper, the upperextractor drum has also withdrawn another signature 212 from the upperhopper. In addition, the vacuum has been applied to the suction cups atthe lower hopper so that the lower extractor drum may also begin towithdraw signatures from this hopper.

In FIG. 11c the upper and lower extractor drums have each rotatedapproximately one quarter turn,

whereas the transfer drum and opener drum have each rotatedapproximately one-half turn. As may be seen, the signature 212 has beencompletely withdrawn from the upper hopper by the upper extractor drum.In addition, the lower extractor drum has clamped a signature 214 andhas partially withdrawn it from the lower hopper. The transfer drum andthe opener drum have drawn the signature 210 downward and have openedits two legs in preparation for dropping it on the saddle.

In FIG. 11d the signature inserter has released the signature 210 andhas withdrawn an additional signature 216 from the upper hopper.Signatures 212 and 214 have been rotated around on their respectiveextractor drums approximately one quater turn.

In FIG. lle the signature inserter has withdrawn a new signature 218from the lower hopper and has rotated the signatures 214 and 216approximately one quarter turn on their respective extractor drums. Thesignature 212 has been drawn downward by the transfer drum and openerdrum and is about to be dropped on the saddle. Vacuum applied to thesuction cups at the upper hopper has been switched off but the vacuumcontinues to be applied to the suction cups at the lower hopper.

The signature inserter is now operating to withdraw signatures from thelower hopper only. FIG. 11f illustrates how these signatures aretransferred from the lower extractor drum to the upper extractor drum bythe intermediate drum. In this case, the signature 214 was released bythe lower extractor drum and clamped by the intermediate drum. Theintermediate drum has drawn the signature 214 upward to the positionshown in FIG. 11f in readiness for clamping by the upper extractor drum.

It will be appreciated from the above discussion of the operation of thesignature inserter that signatures withdrawn from the lower hopperrequire some time to be brought upward to the position at which they areclamped by the upper extractor drum. In particular, the signatureswithdrawn from the lower hopper must be withdrawn I-Vz book cycles aheadof signatures withdrawn from the upper hopper to bring them to the pointof transfer between the intermediate drum and the upper extractor drum.

Thus, when switching from the mode of operation in which signatures arewithdrawn from the upper hopper to the mode in which signatures arewithdrawn from the lower hopper, it is necessary to apply a vacuum tothe suction cups at the lower hopper l-l cycles prior to the time atwhich the vacuum applied to the suction cups at the upper hopper isremoved. Conversely, when switching from the mode of operation in whichsignatures are withdrawn from the lower hopper to the mode in which theyare withdrawn from the upper hooper, it is necessary to remove thevacuum from the suction cups at the lower hopper l-% cycles in advanceof the application of vacuum to the suction cups at the upper hopper.

FIG. 12 illustrates an exemplary embodiment of a logic circuit 200 whichmay be used to actuate the solenoid valves 202 and 204 in the vacuumline to the suction cups 84 and 86 at the upper and lower hoppers,respectively. The control functionsin this circuit are executed by aplurality of electronic gates. It will be understood, however, that anysuitable logic circuit may be substituted for the circuit shown. Forexample, the logic circuit may be comprised of a plurality of relays andassociated contactors forming a conventional switching circuit or it maybe formed of a plurality of fluidic gates interconnected by fluidicpaths forming an equivalent fluidic circuit. In the latter case,fluidactuated valves may be employed in place of the solenoid valves 202and 204 to control the vacuum at the suction cups.

In the circuit sh'own, a timing wheel 220 is employed to synchronize thecircuit operation with the mechanical operation of the signatureinserter. The timing wheel 220 is driven in 1:1 relationship with theintermediate drum 30; that is, the timing wheel makes one revolution perbook cycle of the signature gathering machine. During each revolution,the timing wheel interrupts the voltage V applied to lines 222 and 224through limit switches 226 and 228, respectively.

Reset pulses may be applied to lines 230 and 232 by momentarily pressingreset buttons 234 and 236, respectively. When the machine is turned onand a voltage is originally applied to the logic circuit, the circuitgates should be manually set to their proper states by depressing eitherone of the reset buttons 234 or 236. The reset button 234 sets thecircuit to cause signatures to be withdrawn from the lower hopperwhereas the reset button 236 sets the circuit to cause signatures to bewithdrawn from the upper hopper.

During operation, the logic circuit may be switched either manually orautomatically from upper hopper operation to lower hopper operation-orvice-versa. The circuit may be manually switched to cause withdrawal ofsignatures from the upper hopper by pressing the push button 238.Similarly, the circuit may be manually switched to cause signatures tobe withdrawn from the lower hopper by pressing the push button 240. Thelogic circuit may be switched automatically either to upper hopper orlower hopper operation by applying a logical l (a pulse of voltate V) toeither terminal W or Z, respectively, of gates 241 and 243.-

The two solenoid valves 202 and 204 are normally closed so that a vacuumwill be applied to the respective suction cups only if a voltage isapplied to the valves. As will be understood from the above discussionof the operation of the signature inserter in connection with FIG. 11,the machine cannot be instantaneously switched from upper hopperoperation to lower hopper operation, or vice-versa. Specifically, thesignal applied to the logic circuit indicating a switch from one mode ofoperation to the other must anticipate the actual change-over by I-%book cycles. Stated another way, an input signal indicating a switchfrom one mode of operation to the other sets in motion a switching cyclewhich takes lv book cycles to complete. This switching cycle will now beexplained with reference to FIG. 13.

As noted above, the logic circuit shown in the exemplary embodiment ofFIG. 12 consists of a plurality of electronic gates, referenced 241-272.These gates are so-called NOR-gates: they produce a logical 1" output ifand only if a logical 0 appears at each input. Typical outputs of thesevarious gates are illustrated in FIG. 13 which is an exemplary timingdiagram of the entire logic circuit 200.

Also shown in FIG. 13 are representative signals pro duced by the limitswitches 226 and 228 and, at the bottom of the figure, the reset buttons234 and 236.

At the start of the time period illustrated in FIG. 13 the signatureinserter is operating to withdraw signatures from the lower hopper. Thetiming wheel 220 is in the position shown in FIG. 12 so that the limitswitch 226 has opened the circuit from the voltage supply V to the line222, and the voltage on line 222 is zero. The limit switch 228 isclosed, however, so that the voltage V appears on line 224.

At time T the limit switch 226 is allowed to close, switching on thevoltage V to the line 222. This voltage is applied to gates 242 and 246;however, there is no change in the output of these gates since an inputvoltage is also applied thereto via gates 241 and 243, respectively.

At time T, the push button 238 is momentarily depressed signaling achange in the mode of operation of the signature inserter from withdrawlof signatures from the lower hopper to withdrawal of signatures from theupper hopper. The push button 238 applies an input to gate 241, causingthis gate to drop its output to zero. No change of state of any othergate occurs until time T when the limit switch 226 turns off the inputvoltage to the gates 242 and 246. Since none of the three inputterminals of gate 242 receives a voltage or logical 1, this gate willproduce an output until time T when the limit switch 226 is allowed toclose. An output from gate 242 inhibits the output produced by gate 244which, in turn, allows gate 248 to produce an output. The disappearanceof an output from gate 244 also allows the solenoid valve 204 to returnto its normally closed position. The closing of valve 204 removes thevacuum from the suction cups 86 at the lower hopper preventing thefurther withdrawal of signatures.

At time T, the limit switch 228 is opened switching off the voltage online 224. The absence of an input at gate 254 causes this gate toproduce an output which, in turn, inhibits the output from gate 252.Loss of an output from gate 252 permits gate 256 to produce an output.This output is fed back to gate 252 so that gate 252 will not change itsstate when the input received from gate 254 disappears. Gate 254 losesits output at time T when the limit switch 228 is allowed to close.

The next sequence of the events occurs at time T when the limit switch226 is opened. The gate 262, which has lost an input from gate 252, isnow allowed to produce an output due to the loss of voltage on line 222.This output, which is produced until time T, when limit switch 226 isallowed to close, inhibits the output produced by gate 260. The loss ofthis output causes gate 264 to produce an output which, in turn, isimpressed on an input of gate 260, so that gate 260 will not change itsstate when the input received from gate 262 disappears.

At time T the limit switch 228 is again opened, removing the voltagefrom line 224. Since gate 270 now receives no input from gate 260, lossof the voltage on line 224 causes gate 270 to produce an output. Thisoutput continues until time T when the limit switch 228 is allowed toclose.

The output voltage from gate 270 is impressed on an input of gate 268causing the output of gate 268 to disappear. The loss of the output fromgate 268 permits gate 272 to produce an output which, in turn, issupplied to an input of gate 268 so that gate 268 will not change itsstate at time T upon the disappearance of the output from gate 270.

The output from gate 272 is impressed on and opens the solenoid valve202. A path of vacuum is therefore opened to the suction cups 84 at theupper hopper 14 causing signatures to be withdrawn from this hopper.

As is indicated at the bottom of FIG. 13, the period between the timethat the vacuum is removed from the suction cups 86 at the lower hopperto the time that the vacuum is applied to the suction cups 84 at theupper hopper is exactly 1- /2 book cycles. This delay fulfills therequirements of the signature inserter discussed above which are due tothe difference in the length of signature travel from the upper andlower hoppers to the point of transfer between the intermediate drum 30and the upper extractor drum 24.

After the change of inode of operation of the signature inserter whichwas initiated by pressing the button 238 at time T and which wascompleted when the output of gate 270 fell to a logical 0 at time T thesignature inserter can continue to operate indefinitely in this new modein which it withdraws signatures from the upper hopper. Thus, each ofthe gates 241-272 will remain in the states which are shown at time TIf, at any time, the power to the logic circuit is switched off, thecircuit gates may be reset to the states which occurred at time T whenthe signature inserter was operating to withdraw signatures from thelower hopper, or reset to the states which occurred at time T when thesignature inserter was operating to withdraw signatures from the upperhopper. Resetting the states of the gates to the configuration requiredto withdraw signatures from the lower hopper is accomplished bymomentarily depressing the reset buttons 234. Resetting the states ofthe gates to the configuration required to withdraw signatures from theupper hopper is accomplished by momentarily depressing the reset button236. When the buttons 234 and 236 are depressed, a voltage is applied tolines 230 and 232, re spectively; this voltage is impressed on theinputs of various ones of the gates 241-272 to set all the gates of thecircuit to the desired states.

Once the signature inserter is operating to Withdraw signatures from theupper hopper and the push button 240 is depressed, the states of thegates 244, 248, 252, 256, 260, 264, 268 and 272, will be changed duringa 1- /2 book cycle period in the same operational sequence as thechanges which occurred when the signature inserter was switched from thelower to upper hopper operation. Specifically, after depressing thebutton 240 at time T the gate 246 causes gate 248 and, in turn, gate 244to change their states. Gate 244 produces an output which opens thesolenoid valve 204 to apply a vacuum to the suction cups 86 at the lowerhopper. Thereafter, at time T the gate 250, gate 256 and, in turn, gate252 change their states in response to a logical 0 produced on line 224by the limit switch 228. Subsequently, at time T the gates 258, 264, and260 change their states in response to a logical 0" on line 222 producedby the limit switch .226. Finally, at time T the gates 266, 272, and 268change their states in response to a logical 0 on line 224 produced bythe limit switch 228. The output of gate 272 falls to a logical 0" sothat the solenoid valve 202 can return to its normally closed position,removing the vacuum from the suction cups 84 at the upper hopper.Thereafter, all of the gates 241-272 will retain their states until thepush-button 238 is next depressed to again change the mode of operationof the signature inserter.

The description of the preferred embodiments of the signature inserteraccording to the present invention is not complete. However, it will beappreciated that these preferred embodiments are susceptible to variouschanges, modifications, variations and adaptations as will occur tothose skilled in the art.

For example, whereas the lower extractor drum 26 has been illustratedand described as having the same diameter as the upper extractor drum24, it may be desirable to construct the lower extractor drum with aslightly larger diameter than the upper extractor drum so that thesurface speed of the signatures carried thereby will be slightly greaterthan the surface speed of the signatures carried by the intermediatedrum 30. Thus, at the moment of transfer between the lower extractordrum 26 and the intermediate drum 30, the signatures will beinserted inpositive fashion beneath the gripper fingers 102 so that the opening andclosing action, respectively, of the gripper fingers 94 and 102 need notbe as critically timed to effect the signature transfer.

Similarly, it may be preferable to slightly increase the diameter of theintermediate drum 30 relative to the diameter shown so that the surfacespeed of the signatures carried by the intermediate drum will beslightly greater than the surface speed of the signatures carried by theupper extractor drum 24. As in the case of the transfer between thelower extractor drum 26 and the intermediate drum 30, the slow-down ofthe signatures at the moment of transfer between the intermediate drumand the upper extractor drum 24 will make the transfer more positive andpermit the transferring gripper fingers to be opened and closed lessabruptly.

The preferred embodiments of the signature inserter described above maybe further modified, for example, by providing means for declutching thelower extractor drum 26, the intermediate drum 30 and the cam shaft 53when feeding signatures from the upper hopper 14. By silencing theextracting and transferring mechanisms for the lower hopper, thesignature inserter may be operated without wear to these parts so thatthe entire machine will function in the conventional manner to supplysignatures to the conveyor 36 from the upper hopper only.

The preferred embodiments of the signature inserter described above maybe further modified, for example, by connecting additional switch meansin the circuit that powers the solenoid valves 202 and 204 so that bothsolenoid valves may be switched off. With such switch means thesignature inserter may be caused to exhibit three modes of operation: afirst mode in which signatures are extracted from the upper hopper; asecond mode in which signatures are extracted from the lower hopper; anda third mode in which signatures are not extracted from either hopper.

Accordingly, all such changes, modifications, variations, andadaptations are intended to be included within the spirit and scope ofthe following claims.

We claim:

1. A signature inserter for a signature gathering machine comprising, incombination:

A. a first hopper for feeding a supply of signatures;

B. a first rotary extractor drum associated with the said first hopperhaving means for extracting individual signatures from said firsthopper;

C. first signature transfer means, mounted adjacent to said firstextractor drum, for receiving individual signatures in succession fromsaid first extractor drum and transferring them to a conveyor;

D. a second hopper for feeding a supply of signatures,

said second hopper being arranged in a common vertical plane with saidfirst hopper, said vertical plane extending transverse to the axis ofsaid first rotary extractor drum;

E. a second rotary extractor drum associated with the said second hopperhaving means for extracting individual signatures from said secondhopper;

F. second signature transfer means mounted adjacent to said firstextractor drum and said second extractor drum, for receiving individualsignatures in succession from said second extractor drum andtransferring them to said first extractor drum;

G. means associated with said first and second hoppers for selecting theextraction of signatures from said first and second hoppers, saidselecting means comprising means for selectively withdrawing at leastthe leading edge of individual signatures from said first and saidsecond hoppers including:

1. first suction cup means associated with said first hopper, said firstsuction cup means being movable toward and away from the supply of signatures in said first hopper;

2. second suction cup means associated with said second hopper, saidsecond suction cup means being movable toward and away from the supplyof signatures in said second hopper; and

3. means, connected to said first and second suction cup means, forapplying a vacuum thereto, said means for applying a vacuum to saidfirst and second suction cup means comprising, in combination:

a. a source of vacuum;

b. a first control valve, connected between said source of vacuum andsaid first suction cup means, for selectively applying a vacuum to saidfirst suction cup means;

c. a second control valve, connected between said source of vacuum andsaid second suction cup means, for selectively applying a vacuum to saidsecond suction cup means; and

d. control means for actuating said first and second control valves intimed relation to the operation of the signature inserter to control theapplication of vacuum to said first and second suction cup means, saidcontrol means comprising, in combination:

i. switch means for selecting the hopper from which signatures are to beextracted; ii. means for sensing the rotational position of said firstand second extractor drums; and iii. logic circuit means, connected tosaid switch means and to said sensing means, for actuating said firstand second control valves to control the application of vacuum to saidfirst and second suction cup means; whereby said control means isoperative to cause the signature inserter to insert one signature on theconveyor of the signature gathering machine during each cycle ofoperation. 2. The signature inserter defined in claim 1, wherein saidsecond signature transfer means is a rotary drum,

mounted intermediate said first extractor drum and said second extractordrum.

3. The signature inserter defined in claim 2, wherein said intermediatedrum includes gripper means for gripping the leading edge of eachsignature received from said second extractor drum, for holding saidleading edge while said signature is being transferred to said firstextractor drum, and for releasing said leading edge when said signatureis received by said first extractor drum.

4. The signature inserter defined in claim 3, further comprising atleast one roller arranged adjacent to, and to roll with, the surface ofsaid intermediate drum for holding signatures transferred therebyagainst the surface of said intermediate drum, whereby said grippermeans on said intermediate drum may be opened to release the signaturesbefore the leading edge of the signatures are received by said firstextractor drum.

5. The signature inserter defined in claim 3, further comprising'atleast one belt arranged adjacent to said intermediate drum for holdingsignatures transferred thereby against the surface of said intermediatedrum, said at least one belt being movable in the direction of movementof the surface of said intermediate drum to prevent slippage between thesignatures and the belt surfaces.

6. The signature inserter defined in claim 5, wherein said at least onebelt is driven in the direction of movement of, and at the same speed asthe surface of said intermediate drum.

7. The signature inserter defined in claim 1, wherein said first rotaryextractor drum includes gripper means arranged on the drum periphery forgripping individual signatures received from said first hopper and fromsaid second signature transfer means, said gripper means comprising:

first gripper fingers and first cam means, associated therewith, forrepeatedly closing said first gripper fingers as these fingers pass saidfirst hopper, thereby gripping any signature withdrawn from said firsthopper by said selecting means; and second gripper fingers and secondcam means, associated therewith, for repeatedly closing said secondgripper fingers as these fingers pass said second signature transfermeans, thereby gripping any signature withdrawn from said second hopperand transferred to said first rotary extractor drum by said secondsignature transfer means.

@2 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,Dated p 3, 97

Invenmfls) Lachman et a1.

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

P- a rf l 1 First page, 3rd line of Item 50], "Ehlschide" should be%lscheid--5 Col. 9 line 39, "durm" should read --drum--;

line M, "both" should be --Both- C01. 10 line 15, "operation" shouldread --operating--;

Col. 11, line 66, "the" should be -The--;

C01. 13 line 1 4, "quater" should read --quarter--; and

C01. 17 line 3, "not" should read --now--.

Signed and sealed this 1st day of October 1974 (SEAL) Attest:

MCCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner ofPatents

1. A signature inserter for a signature gathering machine comprising, incombination: A. a first hopper for feeding a supply of signatures; B. afirst rotary extractor drum associated with the said first hopper havingmeans for extracting individual signatures from said first hopper; C.first signature transfer means, mounted adjacent to said first extractordrum, for receiving individual signatures in succession from said firstextractor drum and transferring them to a conveyor; D. a second hopperfor feeding a supply of signatures, said second hopper being arranged ina common vertical plane with said first hopper, said vertical planeextending transverse to the axis of said first rotary extractor drum; E.a second rotary extractor drum associated with the said second hopperhaving means for extracting individual signatures from said secondhopper; F. second signature transfer means mounted adjacent to saidfirst extractor drum and said second extractor drum, for receivingindividual signatures in succession from said second extractor drum andtransferring them to said first extractor drum; G. means associated withsaid first and second hoppers for selecting the extraction of signaturesfrom said first and second hoppers, said selecting means comprisingmeans for selectively withdrawing at least the leading edge ofindividual signatures from said first and said second hoppersincluding:
 1. first suction cup means associated with said first hopper,said first suction cup means being movable toward and away from thesupply of signatures in said first hopper;
 2. second suction cup meansassociated with said second hopper, said second suction cup means beingmovable toward and away from the supply of signatures in said secondhopper; and
 3. means, connected to said first and second suction cupmeans, for applying a vacuum thereto, said means for applying a vacuumto said first and second suction cup means comprising, in combination:a. a source of vacuum; b. a first control valve, connected between saidsource of vacuum and said first suction cup means, for selectivelyapplying a vacuum to said first suction cup means; c. a second controlvalve, connected between said source of vacuum and said second suctioncup means, for selectively applying a vacuum to said second suction cupmeans; and d. control means for actuating said first and second controlvalves in timed relation to the operation of the signature inserter tocontrol the application of vacuum to said first and second suction cupmeans, said control means comprising, in combination: i. switch meansfor selecting the hopper from which signatures are to be extracted; ii.means for sensing the rotational position of said first and secondextractor drums; and iii. logic circuit means, connected to said switchmeans and to said sensing means, for actuating said first and secondcontrol valves to control the application of vacuum to said first andsecond suction cup means; whereby said control means is operative tocause the signature inserter to insert one signature on the conveyor ofthe signature gathering machine during each cycle of operation. 2.second suction cup means associated with said second hopper, said secondsuction cup means being movable toward and away from the supply ofsignatures in said second hopper; and
 2. The signature inserter definedin claim 1, wherein said second signature transfer means is a rotarydrum, mounted intermediate said first extractor drum and said secondextractor drum.
 3. means, connected to said first and second suction cupmeans, for applying a vacuum thereto, said means for applying a vacuumto said first and second suction cup means comprising, in combination:a. a source of vacuum; b. a first control valve, connected between saidsource of vacuum and said first suction cup means, for selectivelyapplying a vacuum to said first suction cup means; c. a second controlvalve, connected between said source of vacuum and said second suctioncup means, for selectively applying a vacuum to said second suction cupmeans; and d. control means for actuating said first and second controlvalves in timed relation to the operation of the signature inserter tocontrol the application of vacuum to said first and second suction cupmeans, said control means comprising, in combination: i. switch meansfor selecting the hopper from which signatures are to be extracted; ii.means for sensing the rotational position of said first and secondextractor drums; and iii. logic circuit means, connected to said switchmeans and to said sensing means, for actuating said first and secondcontrol valves to control the application of vacuum to said first andsecond suction cup means; whereby said control means is operative tocause the signature inserter to insert one signature on the conveyor ofthe signature gathering machine during each cycle of operation.
 3. Thesignature inserter defined in claim 2, wherein said intermediate drumincludes gripper means for gripping the leading edge of each signaturereceived from said second extractor drum, for holding said leading edgewhile said signature is being transferred to said first extractor drum,and for releasing said leading edge when said signature is received bysaid first extractor drum.
 4. The signature inserter defined in claim 3,further comprising at least one roller arranged adjacent to, and to rollwith, the surface of said intermediate drum for holding signaturestransferred thereby against the surface of said intermediate drum,whereby said gripper means on said intermediate drum may be opened torelease the signatures before the leading edge of the signatures arereceived by said first extractor drum.
 5. The signature inserter definedin claim 3, further comprising at least one belt arranged adjacent tosaid intermediate drum for holding signatures transferred therebyagainst the surface of said intermediate drum, said at least one beltbeing movable in the direction of movement of the surface of saidintermediate drum to prevent slippage between the signatures and thebelt surfaces.
 6. The signature inserter defined in claim 5, whereinsaid at least one belt is driven in the direction of movement of, and atthe same speed as the surface of said intermediate drum.
 7. Thesignature inserter defined in claim 1, wherein said first rotaryextractor drum includes gripper means arranged on the drum periphery forgripping individual signatures received from said first hopper and fromsaid second signature transfer means, said gripper means comprising:first gripper fingers and first cam means, associated therewith, forrepeatedly closing said first gripper fingers as these fingers pass saidfirst hopper, thereby gripping any signature withdrawn from said firsthopper by said selecting means; and second gripper fingers and secondcam means, associated therewith, for repeatedly closing said secondgripper fingers as these fingers pass said second signature transfermeans, thereby gripping any signature withdrawn from said second hopperand transferred to said first rotary extractor drum by said secondsignature transfer means.